We report the hyperfine-resolved rotational spectrum of gas-phase phenoxy radical
in the 8–25 GHz frequency range using cavity Fourier transform microwave spectroscopy.
A complete assignment of its complex but well-resolved fine and hyperfine
splittings has yielded a precisely determined set of rotational constants, spin-rotation
parameters, and nuclear hyperfine coupling constants. These results are interpreted
with support from high-level quantum chemical calculations to gain detailed insight into
the distribution of the unpaired π electron in this prototypical resonance-stabilized
radical. The accurate laboratory rest frequencies enable studies of the chemistry of
phenoxy in both the laboratory and in space. The prospects of extending the present
experimental and theoretical techniques to investigate the rotational spectra of isotopic
variants and structural isomers of phenoxy and other important gas-phase radical intermediates
yet undetected at radio wavelengths are discussed.
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This content will become publicly available on May 16, 2025
Rotational Spectrum of the Phenoxy Radical
We report the hyperfine-resolved rotational spectrum of the gas-phase phenoxy
radical in the 8−25 GHz frequency range using cavity Fourier transform microwave spectroscopy.
A complete assignment of its complex but well-resolved fine and hyperfine splittings yielded a
precisely determined set of rotational constants, spin-rotation parameters, and nuclear hyperfine
coupling constants. These results are interpreted with support from high-level quantum chemical
calculations to gain detailed insight into the distribution of the unpaired π electron in this
prototypical resonance-stabilized radical. The accurate laboratory rest frequencies enable studies
of the chemistry of phenoxy in both the laboratory and space. The prospects of extending the
present experimental and theoretical techniques to investigate the rotational spectra of isotopic
variants and structural isomers of phenoxy and other important gas-phase radical intermediates
that are yet undetected at radio wavelengths are discussed.
more »
« less
- NSF-PAR ID:
- 10522065
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- The Journal of Physical Chemistry Letters
- Volume:
- 15
- Issue:
- 19
- ISSN:
- 1948-7185
- Page Range / eLocation ID:
- 5063 to 5069
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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